1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2024 Linaro Ltd. 4 */ 5 6 #include <linux/device.h> 7 #include <linux/module.h> 8 #include <linux/pci-pwrctrl.h> 9 #include <linux/platform_device.h> 10 #include <linux/property.h> 11 #include <linux/pwrseq/consumer.h> 12 #include <linux/slab.h> 13 #include <linux/types.h> 14 15 struct pwrseq_pwrctrl { 16 struct pci_pwrctrl pwrctrl; 17 struct pwrseq_desc *pwrseq; 18 }; 19 20 struct pwrseq_pwrctrl_pdata { 21 const char *target; 22 /* 23 * Called before doing anything else to perform device-specific 24 * verification between requesting the power sequencing handle. 25 */ 26 int (*validate_device)(struct device *dev); 27 }; 28 29 static int pwrseq_pwrctrl_qcm_wcn_validate_device(struct device *dev) 30 { 31 /* 32 * Old device trees for some platforms already define wifi nodes for 33 * the WCN family of chips since before power sequencing was added 34 * upstream. 35 * 36 * These nodes don't consume the regulator outputs from the PMU, and 37 * if we allow this driver to bind to one of such "incomplete" nodes, 38 * we'll see a kernel log error about the indefinite probe deferral. 39 * 40 * Check the existence of the regulator supply that exists on all 41 * WCN models before moving forward. 42 */ 43 if (!device_property_present(dev, "vddaon-supply")) 44 return -ENODEV; 45 46 return 0; 47 } 48 49 static const struct pwrseq_pwrctrl_pdata pwrseq_pwrctrl_qcom_wcn_pdata = { 50 .target = "wlan", 51 .validate_device = pwrseq_pwrctrl_qcm_wcn_validate_device, 52 }; 53 54 static int pwrseq_pwrctrl_power_on(struct pci_pwrctrl *pwrctrl) 55 { 56 struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl, 57 struct pwrseq_pwrctrl, pwrctrl); 58 59 return pwrseq_enable(pwrseq->pwrseq); 60 } 61 62 static int pwrseq_pwrctrl_power_off(struct pci_pwrctrl *pwrctrl) 63 { 64 struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl, 65 struct pwrseq_pwrctrl, pwrctrl); 66 67 return pwrseq_disable(pwrseq->pwrseq); 68 } 69 70 static int pwrseq_pwrctrl_probe(struct platform_device *pdev) 71 { 72 const struct pwrseq_pwrctrl_pdata *pdata; 73 struct pwrseq_pwrctrl *pwrseq; 74 struct device *dev = &pdev->dev; 75 int ret; 76 77 pdata = device_get_match_data(dev); 78 if (!pdata || !pdata->target) 79 return -EINVAL; 80 81 if (pdata->validate_device) { 82 ret = pdata->validate_device(dev); 83 if (ret) 84 return ret; 85 } 86 87 pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL); 88 if (!pwrseq) 89 return -ENOMEM; 90 91 pwrseq->pwrseq = devm_pwrseq_get(dev, pdata->target); 92 if (IS_ERR(pwrseq->pwrseq)) 93 return dev_err_probe(dev, PTR_ERR(pwrseq->pwrseq), 94 "Failed to get the power sequencer\n"); 95 96 pwrseq->pwrctrl.power_on = pwrseq_pwrctrl_power_on; 97 pwrseq->pwrctrl.power_off = pwrseq_pwrctrl_power_off; 98 99 pci_pwrctrl_init(&pwrseq->pwrctrl, dev); 100 101 ret = devm_pci_pwrctrl_device_set_ready(dev, &pwrseq->pwrctrl); 102 if (ret) 103 return dev_err_probe(dev, ret, 104 "Failed to register the pwrctrl wrapper\n"); 105 106 return 0; 107 } 108 109 static const struct of_device_id pwrseq_pwrctrl_of_match[] = { 110 { 111 /* ATH11K in QCA6390 package. */ 112 .compatible = "pci17cb,1101", 113 .data = &pwrseq_pwrctrl_qcom_wcn_pdata, 114 }, 115 { 116 /* ATH11K in WCN6855 package. */ 117 .compatible = "pci17cb,1103", 118 .data = &pwrseq_pwrctrl_qcom_wcn_pdata, 119 }, 120 { 121 /* ATH12K in WCN7850 package. */ 122 .compatible = "pci17cb,1107", 123 .data = &pwrseq_pwrctrl_qcom_wcn_pdata, 124 }, 125 { } 126 }; 127 MODULE_DEVICE_TABLE(of, pwrseq_pwrctrl_of_match); 128 129 static struct platform_driver pwrseq_pwrctrl_driver = { 130 .driver = { 131 .name = "pci-pwrctrl-pwrseq", 132 .of_match_table = pwrseq_pwrctrl_of_match, 133 }, 134 .probe = pwrseq_pwrctrl_probe, 135 }; 136 module_platform_driver(pwrseq_pwrctrl_driver); 137 138 MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>"); 139 MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices"); 140 MODULE_LICENSE("GPL"); 141